| Bell Decor Limited | Construction | 2021 |
| Belmont Health (NI) Limited | Wholesale & retail | 2007 |
| Belmont Meats Limited | Real estate | 1982 |
| BEM Developments Ltd | Households | 2025 |
| Bera Properties Limited | Real estate | 2020 |
| Bespra Ltd | Manufacturing | 2018 |
| Best Irish Used Clothing UK Limited | Wholesale & retail | 2020 |
| Beár NA Cultúrlainne Limited | Wholesale & retail | 2018 |
| Bicycle Face Ltd | Information & communication | 2017 |
| Big Box Commercial Interiors Limited | Wholesale & retail | 2019 |
| Big Deal Outdoors Ltd. | Real estate | 2014 |
| Bigwood Leadership and Development Ltd | Health & social care | 2025 |
| Bingham Energy Limited | Energy | 2016 |
| Bingham Farms Limited | Agriculture & fishing | 2025 |
| Bishop Street Youth Club Ltd | Other services | 2022 |
| Bishops Kitchen Derry Ltd | Hospitality | 2024 |
| Blackthorn Trading (NI) Ltd | Wholesale & retail | 2023 |
| Blackwood Investments (Fairmont) Limited | Construction | 2026 |
| Blast Furnace Recording Studios Limited | Arts & recreation | 1995 |
| BLC Optical Limited | Professional & scientific | 2019 |
| Bloody Sunday Trust - the | Arts & recreation | 2000 |
| Blue Canvas AI Ltd | Professional & scientific | 2026 |
| Bmac Welding Ltd | Manufacturing | 2026 |
| Bobbie Bell Properties Limited | Real estate | 1977 |
| Bogside History Tours Ltd | Administrative & support | 2025 |
| Bokane Ltd | Health & social care | 2024 |
| Borderbuys Ltd | Wholesale & retail | 2022 |
| Boulderstone Ltd | Construction | 2024 |
| Bpss Construction Limited | Construction | 2026 |
| Bradex Ltd | Transport & logistics | 2023 |
| Bradley & Mclaughlin Funeral Directors Ltd | Other services | 2017 |
| Brantley Limited | Real estate | 2015 |
| Brassneck Productions Limited | Information & communication | 2006 |
| Brian Devine Homes Ltd | Construction | 2002 |
| Brickkiln Civil Engineering Contractors Limited | Water & waste | 1991 |
| Brickkiln Skip Hire Ltd | Water & waste | 2015 |
| Brickworx Contracts Ltd | Construction | 2011 |
| Bridge Street Developments Limited | Real estate | 2025 |
| Bridgebrook Ltd | Health & social care | 2023 |
| Bridgehill Property Group Ltd | Construction | 2019 |
| Britewater Environmental (NI) Limited | Water & waste | 2020 |
| Broad Enterprises Limited | Real estate | 1990 |
| Brook Bidco I Limited | Financial services | 2021 |
| Brook Street Projects Ltd | Real estate | 2020 |
| Brookmount Health Limited | Wholesale & retail | 2013 |
| Browne Scaffolding & Labour Limited | Construction | 2019 |
| Bryson Engineering Limited | Professional & scientific | 2022 |
| BS North West Ltd | Real estate | 2022 |
| Bubblebum (UK) Limited | Manufacturing | 2009 |
| Bubbles Laundries Limited | Other services | 2010 |
| Building 31 Hospitality Ltd | Hospitality | 2024 |
| Bulaba Properties Ltd | Real estate | 2024 |
| Burbun UK Limited | Hospitality | 2018 |
| Burke Property Management Ltd | Real estate | 2013 |
| Business Development Agency Services Ltd | Real estate | 1999 |
| Bytes Digital Innovation Limited | Information & communication | 2024 |
| Bzuvi Ltd | Hospitality | 2024 |
| C & W Systems Ltd | Construction | 2006 |
| C Neeson Consulting Limited | Financial services | 2017 |
| C.Lynch Property Investments Ltd | Real estate | 2024 |
| Caam Investments Limited | Real estate | 2025 |
| Cabinhill Developments Limited | Construction | 2024 |
| Cacb Ltd | Real estate | 2022 |
| Caemt Investments Limited | Real estate | 2023 |
| Caldwell National Ltd | Health & social care | 2025 |
| Callaghan Accountancy Services Limited | Professional & scientific | 2022 |
| Calmore Investment | Financial services | 2025 |
| Camowen (Omagh) Limited | Construction | 2024 |
| Campsie Textile Company Limited | Wholesale & retail | 2006 |
| Camrem Limited | Water & waste | 2018 |
| Cantilena Pictures Ltd | Information & communication | 2021 |
| Canvas Monkey Ltd | Manufacturing | 2021 |
| Canvas Supply Co Ltd | Manufacturing | 2020 |
| Caolan's Street Food Limited | Hospitality | 2024 |
| Cappagh Hill Group Limited | Professional & scientific | 2017 |
| Carlin Plant Limited | Construction | 2024 |
| Cassidy Miskelly Ltd | Health & social care | 2019 |
| Castle Gate Apartments Ltd | Real estate | 2025 |
| Castle Old Road Ltd | Real estate | 2019 |
| CC Pipe Designs Ltd | Professional & scientific | 2021 |
| CCC Ltd | Construction | 2020 |
| Cdni Limited | Construction | 2022 |
| CDP GAS Limited | Manufacturing | 2023 |
| Celtronic Derry Ltd. | Arts & recreation | 2012 |
| Century Investments Limited | Real estate | 2009 |
| Cest Interior Design Ltd | Professional & scientific | 2025 |
| CG Contract Cabling Ltd | Construction | 2019 |
| Charlene MCG Services Limited | Professional & scientific | 2025 |
| Charles Court Management Company (Limavady) Ltd | Households | 2021 |
| Chris Hepburn Ltd | Construction | 2023 |
| Churchill Stone (N.I.) Limited | Mining & quarrying | 2011 |
| Ciara and John Holdings Limited | Wholesale & retail | 2023 |
| Cillcara Properties Ltd | Real estate | 2024 |
| Circa Art Magazine | Information & communication | 1987 |
| City Auto Wholesale Limited | Wholesale & retail | 2017 |
| City of Derry International Choir Festival Limited | Education | 2017 |
| City Paints & Wallpapers Ltd | Wholesale & retail | 2017 |
| City Roofing and Asphalt Services Limited | Construction | 1983 |
| Cityprint (Derry) Ltd | Manufacturing | 2019 |
| Cityside Amusements Limited | Arts & recreation | 1998 |